A fundamental problem in the design in any beamformer array is the trade off in array performance versus total array hardware. The larger an array's aperture, the greater the array's resolution. The more fully filled the aperture is with sensors, the more precise is the array's response. (An aperture is fully filled if it has sensors located at intervals of one-half the wavelength of the midband frequency for which the aperture is designed.) However, each sensor in the array and its associated processing circuitry constitutes a considerable amount of hardware. The greater the number of sensors in an array, the greater the hardware in the array, and the greater the system costs. For practical systems, the cost per sensor leg can be great, and decreasing the total number of legs required to achieve the same result can drastically reduce the cost of a system. Sparse (not fully filled) arrays do not produce unique detection beams, but rather tend to produce grating lobes that replicate throughout 180.degree. of look angles. Although such an array can detect the presence of a signal emitter, because of the replication of grating lobes it cannot readily determine from which direction the emitter is signaling, making target estimation (location) impossible. These problems are touched upon in the inventors's paper, "Large-Aperture Sparse Array Antenna Systems of Moderate Bandwidth for Multiple Emitter Location", Memorandum Report of the U.S. Naval Research Laboratory No. 6109, the substance of which is incorporated herein by reference.